I was wrong about 5090 not being bottlenecked by PCIe 4.0
There has been some debate about PCIe 4.0 causing a slowdown with the 5090. Many, including myself thought that wasn't going to be the case because the 4090 wasn't slowed down more than 3% or so when paired with a PCIe 3.0 slot.
I thought it wouldn't matter was well.
I was wrong.
Looks like the 5090 is a hungry beast that really likes bandwidth and it seems to be worse at 1400p vs 4K.